Conventional automatic washers and dryers available in public laundromats are not adapted to be locked by patrons of the laundromat. Consequently, patrons cannot leave their laundry unattended in the washer or dryer without fear of having their laundry tampered with.
Washers or dryers found in publicly available laundromats conventionally have outwardly opening doors. In the prior art, timed door locks for locking outwardly opening doors typically use timers regulating electrically driven deadbolts, or timers regulating the manual operation of a mechanical latch or bolt mechanism. Mechanical timed door locks also typically utilize rotating cams which operate to sequence the mechanical linkages.
In particular, the applicant is aware of the following possibly pertinent patents disclosing various timed door lock devices:
______________________________________ U.S. Pat. No. Inventor Issue Date ______________________________________ 2,960,046 Clark November 15, 1960 3,197,984 Cohen August 3, 1965 3,065,619 Coss November 27, 1962 3,985,023 Guth October 12, 1976 2,991,866 James et al. July 11, 1961 ______________________________________
The Clark patent teaches the use of a time controlled latch mechanism which consists of external linkage which may be added to incinerators and like containers with hinged, outwardly opening doors not previously adapted to receive a locking device. Specifically, Clark discloses a deadbolt arrangement whereby the deadbolt is actuated by a manually operated lever and handle. The deadbolt cooperates with a hole in the outwardly opening door thereby preventing the opening of the door in the manner of a conventional deadbolt. Actuation of the deadbolt is blocked unless the outwardly opening door is properly closed. A timer is provided with a rotating slotted cam. Setting the timer turns the slotted cam which prevents the return of the deadbolt and, consequently prevents unlocking of the outwardly opening door by preventing the movement of the actuating lever until the slot in the cam is realigned with said lever.
Cohen teaches a timer mechanism which may be added externally to a door by the replacement of the keeper or striker of an ordinary latch bolt type of door lock (sometimes referred to as a "Yale" night latch). The latch bolt which ordinarily cooperates with a keeper or striker attached externally to the door frame is replaced by a keeper or striker which only cooperates with the latch bolt according to a preset timer sequence. The keeper or striker consists of an electrically operated solenoid driven plunger. In the embodiment disclosed, the plunger, when placed by the solenoid so as to cooperate with the latch bolt, prevents a door from being opened.
James et al., Coss and Guth all teach locking mechanisms which are necessarily integral to the design of the door being locked. James et al. discloses a spring loaded bolt which cooperates with a notch in a rotating cam, whereby the cam rotates as coins are fed into the mechanism until the notch is aligned with the bolt, and the bolt is returned into the notch allowing the door to be opened. Coss describes an electrically operated solenoid driven plunger which drives a wedge shaped cam, the cam cooperating with a locking bolt, whereby the solenoid actuates the plunger, the wedge cam pulls the bolt back against a return spring, unlocking the door. Guth discloses a rotating cam timer which rotates against a spring loaded lever. A notch in the cam aligns with the lever. Spring action causes the lever to engage a striker linkage which cooperates with the latch mechanism to open the door.